Why Gondor didn't use divide and destroy in 1944

[Hisoka Morrow]

Yes, as Gondor was set as interior stretagy position, it didn't use divide and destroy to handle the 1944 war, such as concentrating all their combat power to annihilate one of the frontal foes but divide it's forces instead or it's my misunderstanding, and it truly did so by having it's major army led by it's king intended originally, while expecting the southern front was the 2nd prior to target? Any JRRT sources can answer this?

 

[wondering]

I am not sure that Gondor could have taken on both attacks entirely separately - all its forces against one, then against another. It seems like the attacks were relatively simultaneous (the Wainriders were still celebrating their northern victory when Earnil arrived from the south) - if Gondor had sent its whole force either south or north, the other enemy army might have been entirely unopposed. Gondor only had two Palantiri at this point (in Minas Anor/Tirith and Minas Ithil) so communications would have been limited to real world pre-industrial speeds, as would the movement of the forces.